1. Field of the Invention
This invention relates to an air gun (air-powered gun). More specifically, the invention relates to an air gun with a retainer for retaining a bullet which moves from a magazine to a propulsion position of an inner barrel.
2. Description of the Related Art
An air gun in this technical field is an air gun where an inner barrel advances in the direction of a muzzle, then the inner barrel retreats to hit a valve, high pressure gas is injected from a gas chamber to the inner barrel by the movement of the valve, and a bullet is discharged.
An air gun having this mechanism is disclosed in U.S. Pat. No. 4,147,152 (related art 1). In this air gun a magazine 20 is placed above an inner barrel 72, and bullets in the magazine 20 are supplied from a loading port 294 to a retainer 160 which is situated under an inner barrel. The retainer 160 is positioned facing the lower part of the loading port 294. The retainer is an elastic body made of a rod-like member inflected. A bullet is supplied to the concave portion of the retainer 160 and retained.
In the related art 1, in order to shoot a bullet, a shooter should push a lever by hand to advance the inner barrel 72 in the direction of the muzzle, the loading port 294 is opened, a bullet in the magazine 20 drops into the inner barrel 72, is retained in the retainer 160, and the bullet is shot by pulling a trigger.
Another air gun (related art 2) with a retainer has been disclosed as shown in FIGS. 22 through 25. Also in the air gun disclosed in the related art 2, a magazine 100 is placed upper part of an inner barrel 102. A bullet W is urged in a direction of the rear side of the air gun by a magazine spring 101. Normally, it is abutted on the upper surface of a tube of the inner barrel 102 and resting. When the bullet W is shot, the inner barrel 102 moves in the direction of a muzzle. After the bullet W is shot, a next bullet drops into a chamber 103 through a magazine loading port placed on the chamber 103. The bullet W dropped in the chamber 103 is retained by a retainer 104 placed at a position opposed to the magazine loading port and biased by a magazine spring 101.
The retainer 104 disclosed in the conventional technology 2 consists of a tube whose upper part is a circular truncated cone, which is biased upward with a retainer spring 105. The upper end of the retainer 104 is formed as a circular opening. The configuration is such that the circular opening pushes upwards and retains the bullet supplied into the chamber 103.
Patent document 1: Patent publication of U.S. Pat. No. 4,147,152 (art 1)
However, the retainer disclosed in the conventional technology 1 is positioned situated under an inner barrel. The retainer (160) is positioned at the lower part of the inner barrel and an elastic body with a concave part made of a rod-like member that is inflected. Therefore, the retainer has a problem that it cannot reliably retain a bullet.
Additionally, in the air gun in the conventional technology 2 the retainer 104 is biased upwards by a retainer spring 105 so that a bullet W positioned at the circular opening is pushed upward. In other words, the bullet is pushed at right angles to the movement of the inner barrel 102. At the same time, the bullet W is pushed by the next bullet W1 from top to bottom by the biasing force of the magazine spring 101 of the magazine 100. Therefore, a biasing force stronger than that of the magazine spring 101 was required for the retainer spring 105.
Thus, the back-end of the inner barrel 102 comes into collision with the upper cone surface of the retainer 104 when the inner barrel 102 moves backwards in the gun, to move the retainer 104 downward, but the upward biasing force of the retainer spring 105 is strong and so the collision is strong, and acts as a resistance to make each member likely to be broken with prolonged use (see FIG. 23).
At the same time, the back-end of the inner barrel 102 also comes into collision with the bullet W in the chamber 103 causing resistance. If the back-end of the inner barrel 102 is deformed, it becomes difficult for the bullet W to be contained in the inner barrel 102 and the bullet cannot be shot due to bullet supply problems. (See FIG. 24).
Further, the upper surface of the cone surface of the retainer 104 always pushes the lower surface of the inner barrel 102 upward of the retainer spring 105 with the biasing force. Therefore, a friction resistance is generated between the upper surface of the cone surface of the retainer 104 and the inner barrel 102 causing members to deteriorate quickly (See FIG. 25).
When the inner barrel 102 moves backward in the gun and comes into collision with the retainer 104 and bullet W, thus reducing the recession velocity of the inner barrel 102 and reducing the force to hit the valve 107. If the force to hit the valve 107 is reduced, the amount of gas discharged from the gas chamber 106 to the inner barrel 102 is decreased or varies so that firing speed of a bullet is reduced, or the original performance of the air gun cannot be demonstrated.
As the related art 2, a bullet is supplied from the upwardly positioned magazine and retained, and so the retainer positioned below the inner barrel has a relatively large size in order to hold the strong upward biasing force, and the retainer positioned above the inner barrel is unnatural from the viewpoint of design of an air gun.